![]() Nitric oxide can also increase the rate of relaxation of cardiac muscles, which is an effect outside of vascular smooth muscles. The end effect of isosorbide mononitrate include decreased cardiac oxygen consumption, redistribution coronary flow toward ischemic areas via collaterals, and the relief of coronary spasms. Reduced cardiac preload and afterload caused by nitric oxide causes a reduction in myocardial oxygen consumption decreased myocardial oxygen demand, along with increased coronary blood flow, leads to an increased in the oxygen content of coronary sinus blood and the relief from ischemia. This leads to increased coronary blood flow. At larger doses, nitric oxide causes the resistance arteries and arterioles to dilate, reducing arterial pressure via coronary vasodilatation. ![]() The direct dilator effect on coronary arteries opposes the coronary artery spasm in variant angina or angina pectoris. Arterial relaxation leads to reduced systemic vascular resistance and systolic blood (aortic) pressure, decreasing to decreased cardiac afterload. In healthy subjects, the stroke volume is decreased and venous pooling can occur in the standing posture, leading to postural hypotension and dizziness.Īt therapeutic doses of isosorbide mononitrate, nitric oxide has a bigger effect on larger muscular arteries over small resistance arteries. Nitric oxide works on both arteries and veins, but predominantly veins: by relaxing veins and reducing the central venous pressure, nitric oxide causes venous pooling and a decrease in the venous return to the heart, thus decreasing cardiac preload. The pharmacological action is mediated by the active metabolite, nitric oxide, which is released when isosorbide mononitrate is metabolized. Isosorbide mononitrate is an anti-anginal agent and vasodilator that relaxes vascular smooth muscle to prevent and manage angina pectoris. ![]() It decreases left ventricular pressure (preload) and arterial resistance (afterload). Isosorbide mononitrate relaxes vascular smooth muscles by stimulating cyclic-GMP. It causes reduction of preload and afterload and redistributes coronary flow to ischemic regions. It is a vasodilator with effects on both arteries and vein and also coronary vessels. Isosorbide-5-mononitrate is an active metabolite of isosorbide dinitrate.
0 Comments
Leave a Reply. |